Whats up everyone, Of course I am new to this site, eventhough I have been reading alot of ya'lls stuff for a couple of weeks. I have an 04 silverado Z71 5.3 with k&n air intake, volocity stack, true daul Magnaflows and a SLP performance Diablo tuner. I guess my Question is, how much extra power are ya'll getting from Nelson tune. Is it better than the programmer that I have, because my programmer woke my truck up. I am kinda interested in one. Oh yeah, the question that everyone ask, does it void warranty